[alsa-devel] [PATCH] ALS4000, slight mixer improvements

[Takashi Iwai]

At Mon, 23 Feb 2009 10:26:36 +0100,
Andreas Mohr wrote:
> 
> Hi,
> 
> On Mon, Feb 23, 2009 at 08:38:12AM +0100, Takashi Iwai wrote:
> > Applied now.  Thanks.
> 
> Thanks!
> 
> > > Will now try to get HDA settings on Aspire One A110L investigated
> > > (using Takashi's elaborate tools) and corrected
> > > (the non-working microphone thingy, plus some weird random switching/activation
> > > of noise in sound sources at times and stuff).
> > 
> > Let me know if it's finished!
> 
> Maybe I should start for real first ;)
> 
> 
> > > Speaking of sound problems, any thoughts about how to end up with
> > > _automatic_, generic ALSA soft volume for those cheap non-hardvol USB sticks?
> [...]
> > 
> > The only problem right now is that the driver might give a real volume
> > control but in a different name.  OTOH, softvol itself isn't too bad as
> > default PCM definition.  Just editing USB-Audio.conf should suffice...
> 
> Probably something like
> http://launchpadlibrarian.net/7244751/USB-Audio.conf
> (referenced by https://bugs.launchpad.net/ubuntu/+source/alsa-lib/+bug/104130 )?
> 
> AFAICS, things should ideally work this way:
> plug USB adapter, ALSA uses its default USB-Audio.conf settings (just like
> with several other PCI and such cards), then for devices with non-existing
> H/W volume (and only those!!), automatically and generically provide ALSA
> softvol.

The "automatically" is easy to write but hard to achieve the guarantee
to work with all possible devices :)

Especially the mixer name of usb-audio is determined dynamically by
guess from usb descriptors, covering all possible names is no easy
task.


Takashi